In an electronic device, sealability of a housing is called for in order for an electronic component housed inside the housing to operate in a stable manner without being affected by the installed environment and the like. Since an electronic component employed in an electronic device is a standard product regardless of the installed environment of the electronic device, the protective function on the housing side is important. In order to reduce entering foreign matters, corrosive gas, and salt into the housing, the housing is formed of a watertight structure, and the housing employs measures such as sealing the gap in the housing with a packing and the like.
Related techniques are disclosed in Japanese Laid-open Patent Publication No. 2003-218572 and Japanese Laid-open Patent Publication No. 2000-101271.